Fuel cells are useful for generating electricity based on an electrochemical reaction. Reactants, such as hydrogen and oxygen, are supplied to the fuel cell using a manifold, for example. One of the challenges associated with manifold design is how to adequately distribute the reactants to the various portions of a cell stack assembly.
For example, air, which is a source of oxygen, is typically supplied into a manifold at a relatively high velocity. The air entering the manifold tends to expand into an enlarged area just inside the manifold inlet. The high velocity of the air stream presents a challenge when attempting to evenly spread the air across the face of the cell stack assembly.
Evenly distributing reactants within a cell stack assembly contributes to increasing the fuel cell operational life and addressing different operating conditions. It is possible with uneven distribution to locally starve portions of a fuel cell stack assembly. The anode and cathode components require an adequate amount of reactant to perform in a desired manner.
Previous attempts at achieving appropriate reactant distribution from a manifold have tended toward adding different channels to the manifold, itself. These approaches introduce additional complexities into the manifold structure. In some cases, the additional manifold complexity does not result in a desired reactant distribution so that little benefit is obtained from the additional complexity